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multiple locations for a lat/lon? RRS feed

  • Question

  • Some time ago, I had asked this question about getting multiple results back for a lat/lon. I was told to just use the first value. However, it appears that this may not be the case. Take the following 2 lat/lon combos:

    53.5215,-113.2539

    http://dev.virtualearth.net/REST/v1/Locations/53.5215,-113.2539?o=xml&inclnb=1&key=[mybingkey]

    53.5215,-113.2535

    http://dev.virtualearth.net/REST/v1/Locations/53.5215,-113.2535?o=xml&inclnb=1&key=[mybingkey]

    In both cases, the return 5 locations. The first two locations are:

    - 200 Foxtail Way, Sherwood Park, AB T8A 2H4, Canada
    - 987 Regency Dr, Sherwood Park, AB T8A 1T6, Canada

    I could use the first location for each lat/lon. However, if I go to bing.com/maps and enter these two lat/lon combos, 53.5215,-113.2539 shows the location as Regency Dr, while 53.5215,-113.2535 shows the location as Foxtail Way. 

    How can I make my call as accurate as bing.com/maps? 

    Thanks.

    Tuesday, December 2, 2014 8:27 PM

Answers

  • Frist off, the consumer site and the development API's should not be compared. They are designed to work differently as developers tend to need more flexibility.

    When it comes to reverse geocoding, it is common to have more than one result as it's an approximation. Most address data on it's own is based on an estimated location. For example, on a road that starts at house number 1 and goes to 100, house 50 would be approximately in the middle of the road. This may or may not be the case, but that is how majority of the of addresses are georeferenced. Bing Maps does have rooftop geocoded data, which is data that someone has physically positioned the coordinate on the roof of the correct building, but this is not available everywhere and takes a long time to capture. As such there is a margin of error when it comes to the placement of addresses. In addition to this reverse geocoding general searches within a radius for locations as it's very unlikely you would know the exact coordinate that is in our database with 12 decimal place accuracy.

    Looking at the coordinates you provided there are several houses in a very small area, and the coordinates are out in the road, which means that there are several driveways very close to the coordinate. This is the reason for having multiple results.

    You could try and add more decimal places. A coordinate with 4 decimal places has an accuracy of +/- 11 meters. With the coordinates you provided there are several homes that are really close together that would fall into this area. You could also try and use a coordinate that is in the on the property rather than on the road.


    http://rbrundritt.wordpress.com

    Wednesday, December 3, 2014 11:26 AM

All replies

  • Frist off, the consumer site and the development API's should not be compared. They are designed to work differently as developers tend to need more flexibility.

    When it comes to reverse geocoding, it is common to have more than one result as it's an approximation. Most address data on it's own is based on an estimated location. For example, on a road that starts at house number 1 and goes to 100, house 50 would be approximately in the middle of the road. This may or may not be the case, but that is how majority of the of addresses are georeferenced. Bing Maps does have rooftop geocoded data, which is data that someone has physically positioned the coordinate on the roof of the correct building, but this is not available everywhere and takes a long time to capture. As such there is a margin of error when it comes to the placement of addresses. In addition to this reverse geocoding general searches within a radius for locations as it's very unlikely you would know the exact coordinate that is in our database with 12 decimal place accuracy.

    Looking at the coordinates you provided there are several houses in a very small area, and the coordinates are out in the road, which means that there are several driveways very close to the coordinate. This is the reason for having multiple results.

    You could try and add more decimal places. A coordinate with 4 decimal places has an accuracy of +/- 11 meters. With the coordinates you provided there are several homes that are really close together that would fall into this area. You could also try and use a coordinate that is in the on the property rather than on the road.


    http://rbrundritt.wordpress.com

    Wednesday, December 3, 2014 11:26 AM
  • thanks Ricky
    Wednesday, December 3, 2014 11:48 AM